Rotatable hot line clamps



July 9, 1963 e. R. GAINER ETAL ROTATABLE HOT LINE CLAMPS Filed May 6. 1960 2 Sheets-Sheet l FHg-Z Fig-1 9G 5 l W W F g 4 INVENTORS 00 1?. mam/51?, 1

United States Patent 3,097,037 ROTATABLE HOT LINE CLAMPS Guy R. Gainer, 3700 W. 16th St., and George A. McLam, 1214 Calhoun Ave., both of Panama City, Fla. Filed May 6, 1960, Ser. No. 27,391 4 Claims. (Q1. 339-445) This invention relates to novel \and improved hot line clamps, wherein hot line clamping components and conductor clamping components, for jumper Wires or ground chains, are rotatable relative to each other.

The primary object of the invention is the provision of hot 'line cl-amps of the kind indicated, which are electrically and mechanically superior, are substantially arcproof, and which greatly facilitate the work of and increase the safety of linemen, by eliminating the need for bending, twisting, or otherwise over-stressing such as jumper wires and ground chains and other secondary conductors, since components of the clamps can be rotated relative to each other into positions corresponding with the positions of the main conductors or hot lines and the secondary conductors, where these are disposed in angular relation to each other.

Another object of the invention is to provide hot line clamps of the character indicated above which assure accurate and secure fitting of the main line clamps on main conductors, and which eliminate loosening and other undesirable strains and stresses on the main line clamping components and the main Lines, otherwise produced by spring-back of secondary conductors which have had to be bent or twisted to engage them in the secondary conductor clamping components.

A further object of the invention is the provision of hot line clamps of the character indicated above, which are uncomplex in construction, the same being composed of a small number of simple and easily assembled parts, and being capable of being produced in rugged and wellfinished forms at relatively low cost.

Other important objects and advantageous features of the invention will be apparent from the following description and the accompanying drawings, wherein, for purposes of illustration only, a specific form of the invention is set forth in detail:

In the drawings:

FIGURE 1 is a side elevation of a hot line clamp of the present invention, showing main and secondary conductors clamped therein;

FIGURE 2 is an edge elevation of said clamp, taken from the right of FIGURE 1;

FIGURE 3 is a transverse vertical section taken on the line 33 of FIGURE 2;

FIGURE 4 is a top plan view of FIGURE 1, showing rotated positions of the components of the clamp, in full and in phantom lines;

FIGURE 5 is a horizontal section taken on the line 5-5 of FIGURE 1;

FIGURE 6 is a side elevation of another form of hot line clamp of the present invention, showing main and secondary conductors clamped therein;

FIGURE 7 is an edge elevation of said clamp, taken from the right of FIGURE 6;

FIGURE 8 is a vertical transverse section taken on the line 8-8 of FIGURE 7;

FIGURE 9 is a horizontal section taken on the line 99 of FIGURE 6; and,

FIGURE 10 is a horizontal section taken on the line lit-A10 of FIGURE 8.

Referring in detail to the drawings, in which like and related numerals designate like and related parts throughout the several views, and first to FIGURES 1 to 5, the hot line clamp therein shown, and generally designated 3,097,037 Patented July 9, 1963 12, comprises a main conductor clamp component 14, and a secondary clamp component 16, which is rotatably mounted on the main clamp component 14, for clamping a main conductor M and a second conductor S, respectively, these components and their parts being made of suitable high-conductive metal.

The main conductor clamp component 14 comprises an elongated straight flat shank 18 on whose other side is a reinforcing and lifting rod eye-carrying flange 20, which is centered on the longitudinal centerline of the shank 18, and has, at its upper end, a lateral eye 22. On the lower end of the shank 18 is a night-angular later-ally inwardly extending arm 24 having a circular boss 26 on its underside, to which is joined an end portion 28 of the eye flange 20. A vertical threaded bore 30 extends through the arm 24 and the boss 26, through which is threaded a clamping screw 32.

The clamping screw 32 has a turning loop or handle 34 fixed on its lower end, below the boss 26, and has a circumferential locking groove 36 located near to and spaced from its flat and squared upper end 38. A movable clamping jaw 40 is engaged over the upper end of the screw 32, and comprises a solid rectangular block 42 having a depending collar 44 on its underside, which, with an indentation 46 in the underside of the block 42, defines a cylindrical downwardly opening socket 43, in which the upper end of the screw 32 is closely and rotatably engaged, and in which it is held by suitable means, such as a pin 50 secured to the block 42 and extending across one side of the socket 48 and engaged in the locking groove 36.

The movable jaw block 42 has, in its top, a transversely extending concavity 52 for engaging a side of a main conductor M. The jaw 40 is guided on the shank 1%, and held against rotation relative thereto, by laterally spaced vertical guide flanges 54, on the laterally outward end 56 of the block 42, which are slidably engaged with related side edges of the shank 18, with the outer end 56 of the block in sliding engagement with the laterally inward side 58 of the shank.

Fixed on the upper end of, and positioned laterally inwardly of the shank 18, is a stationary jaw 69, which is in the form of a vertically elongated solid rectangular block 62, which has, at the side thereof remote from the eye flange 20, a downwardly and laterally outwardlycurved main conductor guide tongue 64, having a convex undersurface 66, for guiding a main conductor between the jaws 40 and 60.

The stationary jaw block 62 is formed with a downwardly opening axial socket which is aligned with the clamping screw 32, and which is composed of a relatively large diameter lower portion 68, and a smaller diameter upper portion 70, the lower end of the larger lower portion 68 being flared, as indicated at 72. The smaller upper socket portion 70 is closed at its upper end by an integral top wall 74, through which is formed an axial bore 76, which is smaller in diameter than the upper socket portion. A swivel stud 78 is engaged in the socket.

The swivel stud 7 8 comprises a cylindrical head 80 which is slightly smaller in diameter than the lower socket portion 68 and larger in diameter than the upper socket portion 70, so that upward movement of the stud in the socket is limited and stopped by engagement of the head 80 with a shoulder 82 which is defined between the lower and upper portions of the socket. Centered on the upper side of the head 80 is a reduced axial boss 84 which is of a diameter to slide and rotate slowly in the upper socket portion 70, without lost motion. Upstanding on the boss 84 is a smooth stem 86, which is smaller in diameter than the boss 84, and which extends slidably and rotatably and closely through the bore 76. The stem 86 has on its 1 its smaller upper end in a shallow bore 76 upper end, above the block 62, a threaded terminal 88. Circumposed on the stem 86, within the upper socket portion 76 is a helical spring 9% which is compressed between the top wall 74 and the boss 84-. The spring 90 serves to push the stud 73 downwardly against a main conductor M engaged between the jaws 4t} and 6%, whenever the movable jaw 40 is moved away from the stationary jaw 69, so that constant and continuous electrical contact is maintained between the stud '78 and the main conductor M, such that arcing therebetween is precluded, which might damage the parts and subject a lineman to electrical shock.

The secondary conductor component 16 of the instant hot line clamp is fixedly mounted on the upper end of the stem 86 of the stud 78. The component 16 comprises a solid rectangular and horizontally or transversely elongated block 92, having a longitudinal bore 94 extending therethrough to freely receive a secondary conductor S, and a set screw 96 is threaded through the top of the block 92 and into the bore 94- to clamp the conductor therein.

The bottom 98 of the block 92 and the top 100 of the stationary jaw block 62 are formed with axially aligned bosses 102 and 104, respectively, which serve to vertically space the blocks 92 and 62 from each other. The facing ends of the bosses 102 and W4 are mating finished surfaces 106 and 108, respectively, which are provided to make eflicient electrical contact with each other, when the clamping screw 32 is loosened enough to permit the spring 90 to expand and force the stud 78 downwardly relative to the stationary jaw block 62, far enough to produce engagement of the bosses 102 and 104 with each other. This feature is provided to positively eliminate electrical arcing between the secondary clamp component block 92 and the stationary jaw block 62, in the situation outlined. Further, the finished and mating ends 106, 108 provide for desirable, easy and relatively frictionless rotation of the components 14 and 16 relative to each other, even while the bosses 102, 104 are forcibly engaged with each other.

The secondary clamp component block 92 is mounted .on the stud 78, preferably by means of a threaded socket 110 formed centrally in its underside, into which the threaded stud terminal 88 is threaded. In order to provide against rotation between the block 92 and the stud 78, any suitable means can be employed, such as swaging the socket 110 around the stud stem 86.

It will be obvious from the foregoing that, with the secondary conductors clamped in the conductor clamp components 16 the main conductor clamp component 14 can be freely rotated, by a lineman, relative to the component 16, to whatever position or positions may be convenient or necessary for facilitating the work of clamping a secondary conductor S, in an unbent and untwisted condition, to the main conductor M.

The form of the hot line clamp shown in FIGURES 6 to 10, and generally designated 12", diifers from the form of FIGURES 1 to 5, only in the construction and relative arrangement of its fixed jaw60 its swivel stud 78 and its secondary conductor clamp component 16*.

The stationary jaw 60 of the hot line clamp 12 is vertically shortened, as compared to the stationary jaw 60, is disc-like in formation and has a convex top 100 and'a transverse concavity 111 in its lower end. Instead of being provided with a socket, the jaw 60 is formed with a downwardly flaring bore 112 which terminates at A laterally outwardly and downwardly extending main conductor guide lip 64 is provided on the side of the jaw 60 remote from the shank 18 and has a convex guide surface 66 on its underside.

The swivel stud 78* has a downwardly flaring head 80*, Whose taper is somewhat less than that of the flared bore 112, and its smooth stem 86 extends upwardly through the shallow bore 7 6 in which the stem is closely and rotatably and slidably engaged, and the stem 86 has a threaded terminal S8 on its upper end. The secondary clamp component 16 comprises a vertically elongated downwardly flaring or frusto-conical block 92 whose larger lower end 162 is larger in diameter than the fixed jaw 60*, and has opening thereto an upwardly tapering axial annular recess 114. The height of the block 92 makes up for the shortening of the fixed jaw 60 so that the secondary conductor clamping component 16 carries a secondary conductor S at substantially the same height above the main conductor M, as is provided for the clamp of FIGURES 1 to 5. An annular downwardly extending flange 116 on the lower end of the block 92 surrrounds and is closely and slidably enagaged with the fixed jaw 60*. The terminal 88 of the swivel stud stem 86 is securably and non-rotatably engaged in a socket 110 provided in the upper end 118 of the recess 114. A helical spring 9% is circumposed on the stem 86 and is compressed between the upper end 118 of the recess 114 and the top 110 of the fixed jaw 60. A transverse secondary conductor accommo dating bore 94- is provided in the upper part of the block 92 above recess 114, and a clamping set screw 96 is threaded into the upper end of the block 92 and enters the bore 94*. The surrounding engagement of the flange 116 with the upper part of the stationary jaw 66 prevents wobbling of the swivel pin 78 when the main clamp component is not fastened to a main conductor, and assures that when the main component is fastened to a main conductor, the secondary olarnp component will be held stationary, the two components being fixed together by the action of clamping the main conductor against the lower end of the swivel stud, so that the three then serve as one conductor.

When the screw 32 is backed off, the spring 90 expands and forces the head 102 of the stud 78 into firm contact with the stationary jaw 644 so that firm and continuous electrical contact is obtained between the swivel stud and a main conductor M engaged between the jaws 60* and 40 and the flange 116, which is normally out of electrical contact with the fixed jaw 60*, is engaged therewith so that arcing between the block 92 and the fixed jaw 60 is eliminated, both in loosening and tightening the clamp.

While there have been shown and described herein preferred forms of the invention, it is to be understood that the invention is not necessarily confined thereto, and that any change or changes in the structure of and in the relative arrangements of components thereof are contemplated as being within the scope of the invention as defined by the claims appended hereto.

What is claimed is:

1. A hot line clamp comprising main conductor clamping component, having an elongated shank having upper and lower ends and laterally inward and outward sides, a fixed jaw on the shank at its upper end and extending laterally inwardly from the shank, an arm on the shank at its lower end and extending laterally inwardly from the shank, a clamping screw threaded through said arm, said screw having an upper end above said arm and a lower end below said arm, means for rotating the screw in opposite directions, a movable jaw rotatably connected on the upper end of the screw in line with the fixed jaw, guide means on the movable jaw slidably engaged with the shank, said fixed jaw having upper and lower ends, vertical opening means extending through said fixed jaw to its ends, shoulder means in said opening means spaced above the lower end of the opening means, a swivel stud engaged upwardly through said opening means, said stud comprising an enlarged head in said opening means 'below and engageable, at times, with said shoulder means and an upstanding smooth stem having an upper end extending above the upper end of the fixed jaw, and a secondary conductor clamping component fixedly and non-rotatably mounted on the upper end of the stem,

and spring means engaged with the stud and biasing the stud head toward the movable jaw, and being compressible to space the secondary conductor clamping component upwardly out of contact with the fixed jaw while the main conductor is clamped between the movable jaw and the fixed jaw and the stud head is in electrical contact with such main conductor.

2. A hot line clamp comprising a main conductor clamping component, having an elongated shank having upper and lower ends and laterally inward and outward sides, a fixed jaw on the shank at its upper end and extending laterally inwardly from the shank, an arm on the shank at its lower end and extending laterally inwardly from the shank, a clamping screw threaded through said arm, said screw having an upper end above said arm and a lower end below said arm, means for rotating the screw in opposite directions, a movable jaw rotatably connected on the upper end of the screw in line with the fixed jaw, guide means on the movable jaw slidably engaged with the shank, said fixed jaw having upper and lower ends, vertical opening means extending through said fixed jaw to its ends, shoulder means in said opening means spaced above the lower end of the opening means, a swivel stud engaged upwardly through said opening means, said stud comprising an enlarged head in said opening means below and engageable, at times, with said shoulder means and an upstanding smooth stem having an upper end extending above the upper end of the fixed jaw, and a secondary conductor clamping fixedly and non-rotatably mounted on the upper end of the stem, and spring means engaged with the stud and biasing the stud head toward the movable jaw, and being compressible to space the secondary conductor clamping component upwardly out of contact with the fixed jaw while a main conductor is clamped between the movable jaw and the fixed jaw and the stud head is in electrical contact with such main conductor, said opening means comprising a socket having a larger diameter lower portion opening to the lower end of the fixed jaw and a smaller diameter upper portion closed at its upper end by a wall at the top of the fixed jaw, said wall having an axial bore therethrough smaller in diameter than said upper socket portion, said stud head sliding in the larger lower socket portion, an upstanding boss on said head slidably and rotatably fitting said upper socket portion, the stud stem extending slidably through said bore, said spring means being a helical spring circumposed on the stem within said upper socket portion and compressed between said top wall and said boss, said upper and lower socket portions defining a shoulder therebetween with which the stud head is, at times, engageable, said secondary component comprising a block having a transverse horizontal bore therethrough to receive a secondary conductor, and means for clamping the secondary conductor therein.

3. A hot line clamp comprising a main conductor clamping component, having an elongated shank having upper and lower ends and laterally inward and outward sides, a fixed jaw on the shank at its upper end and extending laterally inwardly from the shank, an arm on the shank at its lower end and extending laterally inwardly from the shank, a clamping screw threaded through said arm, said screw having an upper end above said arm and a lower end below said arm, means 'for rotating the screw in opposite directions, a movable jaw rotatably connected on the upper end of the screw in line with the fixed jaw, guide means on the movable jaw slidably engaged with the shank, said fixed jaw having upper and lower ends, vertical opening means extending through said fixed jaw to its ends, shoulder means in said opening means spaced above the lower end of the opening means, a swivel stud engaged upwardly through said opening means, said stud comprising an enlarged head in said opening means below and engageable, at times, with said shoulder means and an upstanding smooth stem having an upper end extending above the upper end of the fixed jaw, and a secondary conductor clamping component fixedly and non-rotatably mounted on the upper end of the stern, and spring means engaged with the stud and biasing the stud head toward the movable jaw, and being compressible to space the secondary conductor clamping component upwardly out of contact with the fixed jaw while a main conductor is clamped between the movable jaw and the fixed jaw and the stud head is in. electrical contact with such main conductor, said opening means comprising a socket having a larger diameter lower portion opening to the lower end of the fixed jaw and a smaller diameter upper portion closed at its upper end by a wall at the top of the fixed jaw, said wall having an axial bore therethrough smaller in diameter than said upper socket portion, said stud head sliding in the larger lower socket portion, an upstanding boss on said head sl-idably and rotatably fitting said upper socket portion, and the stud stem sliding through said bore, said spring means being a helical spring circumposed on the stem within said upper socket portion and compressed between said top wall and said boss, said upper and lower socket portions defining a shoulder therebetween with which the stud head is, at times, engageable, said secondary conductor clamping component comprising a block having a transverse horizontal bore therethrough to receive a secondary conductor, and means for clamping the secondary conductor therein, said fixed jaw comprising a block, facing reduced diameter bosses on the secondary conductor clamping block and the fixed jaw block, said bosses being rotatably engaged and spacing the secondary conductor clamping block above the fixed jaw block.

4. A hot line clamp comprising a shank having first and second ends, a lateral fixed jaw on the shank at said first end and at one side of the shank, said fixed jaw having a socket opening to the end thereof adjacent to the second end of the shank, said socket having an end wall provided with an opening, a stud having an enlarged head positioned in the socket and a stem extending slidably through said opening, stop means in said socket limiting travel of the stud toward the first end of the shank, spring means compressed between the fixed jaw and the stud, a transverse secondary conductor clamp fixed on the stem, the secondary conductor clamp and the stud being rotatable relative to the fixed jaw, said fixed jaw having an end facing the second end of the shank and formed with a flared transverse opening extending to opposite sides of the fixed jaw, the adjacent end of the socket opening to the flared opening, said head being exposed within the flared opening, a movable jaw supportably engaged with the shank between the fixed jaw and the second end of the shank, and a clamping screw mounted on the shank and connected to the movable jaw.

References Cited in the file of this patent UNITED STATES PATENTS 369,143 Wihite Aug. 30, 1887 1,793,911 Dann Feb. 24, 1931 2,038,436 Mangin Apr. 21, 1936 2,287,762 Rogofi June 23, 1942 2,448,402 Thompson Aug. 31, 194-8 FOREIGN PATENTS 986,220 France Mar. 21, 1951 

4. A HOT LINE CLAMP COMPRISING A SHANK HAVING FIRST AND SECOND ENDS, A LATERAL FIXED JAW ON THE SHANK AT SAID FIRST END AND AT ONE SIDE OF THE SHANK, SAID FIXED JAW HAVING A SOCKET OPENING TO THE END THEREOF ADJACENT TO THE SECOND END OF THE SHANK, SAID SOCKET HAVING AN END WALL PROVIDED WITH AN OPENING, A STUD HAVING AN ENLARGED HEAD POSITIONED IN THE SOCKET AND A STEM EXTENDING SLIDABLE THROUGH SAID OPENING, STOP MEANS IN SAID SOCKET LIMITING TRAVEL OF THE STUD TOWARD THE FIRST END OF THE SHANK, SPRING MEANS COMPRESSED BETWEEN THE FIXED JAW AND THE STUD, A TRANSVERSE SECONDARY CONDUCTOR CLAMP FIXED ON THE STEM, THE SECONDARY CONDUCTOR CLAMP AND THE STUD BEING ROTATABLE RELATIVE TO THE FIXED JAW, SAID FIXED JAW HAVING AN END FACING THE SECOND END OF THE SHANK AND FORMED WITH A FLARED TRANSVERSE OPENING EXTENDING TO OPPOSITE SIDES OF THE FIXED JAW, THE ADJACENT END OF THE SOCKET OPENING TO THE FLARED OPENING, SAID HEAD BEING EXPOSED WITHIN THE FLARED OPENING, A MOVABLE JAW SUPPORTABLY ENGAGED WITH THE SHANK BETWEEN THE FIXED JAW AND THE SECOND END OF THE SHANK, AND A CLAMPING SCREW MOUNTED ON THE SHANK AND CONNECTED TO THE MOVABLE JAW. 